Judge Mr Justice Sweeney granted Pryce bail until sentencing, a date for which has not been set, when he will also sentence Huhne.

He told the economist, as he had told Huhne, to be under no illusion of what sentence to expect.

"Obviously Ms Pryce was present when I indicated to Mr Huhne the inevitable consequences of a conviction for an offence of this sort.

"She must be under no illusions that my granting of bail indicates any watering down of that provisional approach."

He thanked the jury for discharging their task "assiduously" in a case which could not have been easy.

The Crown Prosecution Service said it would seek costs for the case, after Huhne made repeated legal challenges. "This was expensive for the CPS and we will be applying for costs," said a spokesman.

Pryce's solicitor, Robert Brown, made a statement on her behalf outside the court.

He said: "Mrs Pryce is naturally very disappointed to have been convicted. She would like to thank all those who have supported her during this difficult process, particularly her children, her friends and colleagues.

"Mrs Pryce will return to court to be sentenced in due course. No further comment will be made until this is completed."

The jury's verdict brings a tragic conclusion to the bitter relationship break-up triggered when Huhne left Pryce after 26 years of marriage for his bisexual aide, Carina Trimingham, 46, in the summer of 2010.

Vicky Pryce, centre, leaves Southwark Crown Court after being found guilty of perverting the course of justice (Getty Images)

The speeding points episode would have remained a dirty family secret if Pryce had not decided to "nail" her husband by leaking the story to journalists in revenge for his affair.

Anxious to avoid being prosecuted herself, she at first falsely told reporters that Huhne had made a constituency aide take the points, then tried to ensure that the papers did not report that it was she who accepted responsibility for driving the speeding car.

However, the truth quickly came out and police launched an investigation that resulted in Huhne and Pryce awkwardly sitting side by side in the dock of Court 3 at London's Southwark Crown Court but avoiding even the slightest eye contact with each other.

The former Lib-Dem MP dramatically pleaded guilty and retired from politics on the morning his trial was due to begin after failing to persuade the judge that the charge against him should be thrown out.

Pryce, a mother of five grown-up children, persisted with her claim that she was a victim of marital coercion, a rarely-used defence to criminal offences whereby wives can claim that they were deprived of their freedom to choose by their husbands.

But the jury decided that the high-flying businesswoman and senior civil servant would have been perfectly able to reject her husband's pressure to take the penalty points if she had really wanted to do so.

Greece-born Pryce already had two daughters from her failed first marriage when she met Huhne, then a journalist with The Guardian who had serious political ambitions, in 1982. They married two years later and had three children together.

For most of the time their marriage was a happy one, but there were areas of serious tension over the years.

Pryce claimed that Huhne forced her to have an abortion in 1990 because having another child would have been "bad for his career", but she resisted him when she fell pregnant again two years later and went on to have the baby.

Huhne was an MEP and regarded as a rising star in the Liberal Democrats when he was clocked speeding in his BMW 7 – series at 69mph in a 50mph zone on the M11 in Essex on March 12 2003.

He already had nine penalty points on his licence and so faced an automatic driving ban, which would have jeopardised his chances of winning nomination as the Lib-Dem candidate for the winnable Westminster seat of Eastleigh in Hampshire.

The politician saw a simple way out of his bind by asking his wife, who had a clean licence, to take the points for him.

Pryce, however, was furious at the suggestion that she should help him break the law and refused despite his repeated angry demands.

She told her trial that Huhne eventually dropped the matter and things went quiet until out of the blue she received an official letter saying she had been nominated as the driver of the car when it was caught speeding.

Pryce "exploded" with anger, and after shouting at her husband using Greek swearwords left the letter in the hallway of the family home in Clapham, south London.

By her own account, she came downstairs a day or two later to find Huhne standing there with a pen and the form, which had already been filled in with her name, and insisted that she sign it that instant.

Describing how she finally gave in, Pryce told the jury: "It looked like a complete fait accompli for me and for him. I had been worn down over a period of time and it looked to me like it was the only thing I could possibly do."

However, the prosecution questioned why she had never told anyone else about this moment when she signed the form, and suggested she had made it up after learning that the marital coercion defence depended on the husband being physically present.

The speeding points issue continued to rankle with Pryce, especially after Huhne lost his licence anyway shortly afterwards for using a mobile phone at the wheel and she had to drive him everywhere.

But it was not made public until after the couple's marriage broke down in the most public and humiliating way in June 2010, when Huhne's affair with Miss Trimingham was exposed by the News of the World.

Devastated at this betrayal, Pryce gradually let slip to journalists about the speeding points incident more than seven years earlier.

She first told the Mail on Sunday that Huhne had forced Jo White, one of his constituency aides in Eastleigh, to take his penalty points, but the paper established that this was untrue and the story never appeared.

Then over lunch at a restaurant called Christopher's in Covent Garden, central London, on March 1 2011 Pryce disclosed the full truth to Isabel Oakeshott, The Sunday Times's political editor.

After much negotiation and an attempt to record Huhne confessing to the crime, the story broke in the newspapers just over two months later.

At first Pryce was not named publicly as the person who accepted the points, but she felt she had already been exposed and wanted to "turn the clock back".

However, it was too late. Driven by her desire for revenge, she had set in motion a train of events that would lead not only to her husband's political ruin but also her own downfall.